The invention relates to a battery that may notably be used in the field of electric and hybrid transport and in onboard systems. The invention relates, in particular, to batteries of the lithium-ion (Li-ion) type adapted to these kind of applications, owing to their possibility of storing a high energy with a low mass. The invention is also applicable to super-capacitors.
An electrochemical accumulator has a nominal voltage of the order of a few volts, and more precisely, 3.3 V for Li-ion batteries containing iron phosphate and 4.2 V for a Li-ion technology based on cobalt oxide.
If this voltage is too low with respect to the demands of the system to be powered, several accumulators are placed in series.
It is also possible to dispose, in parallel with each accumulator linked in series, one or more accumulators in order to increase the available capacity and hence to supply a higher current and power. The accumulators associated in parallel thus form a stage. A stage is composed of a minimum of one accumulator. The stages are arranged in series in order to reach the desired voltage level.